The UK's top counter-terrorism officers have issued a fresh plea to British holidaymakers to stay alert for attacks while abroad this summer.
A four-minute safety video advising tourists how to react in the event of a terror attack has been re-launched.
The clip, which was first issued last year, tells people to follow the official "run, hide, tell" guidance.
The chances of being involved in an attack "are still low", said police - but people should "know what to do".
Chief Superintendent Nick Aldworth, of the Metropolitan Police, said: "We want people to think of this in the same way they do the safety film airlines show before take-off.
"They don't expect anything bad to happen but it is a sensible safety precaution to show people what to do."
The video, which was released in July last year and has now been watched by seven million people, outlines what to do during a gun attack at a hotel.
It shows families and hotel staff fleeing the sound of gunshots, barricading themselves into rooms and being treated as potential suspects by armed police.
The clip came two years after the terror attack in the beach resort of Sousse, Tunisia in June 2015, when a gunman killed 38 people, including 30 Britons.
'No need for alarm'
There is no specific information that British people travelling abroad will be targeted this summer, police said.
Security minister Ben Wallace reassured Britons that "there is no need to be alarmed" and the majority will never experience an attack while on holiday.
But he said it is important to "remain vigilant" and watch the video, which could be "life-saving". He also suggested holidaymakers "read the small print on their travel insurance" to ensure they are covered.
Since the Tunisia attack, the number of UK counter-terrorism police liaison officers working overseas has doubled. There are now 46 such officers working abroad, compared with 23 two years ago.
The Foreign and Commonwealth Office urges holidaymakers to read the travel advice for the place they are travelling.
The video has been translated into 15 different languages by the Association of British Travel Agents to brief holiday representatives as well as hotel and security staff.
Police previously released a similar "run, hide, tell" video advising what to do during a terror attack on UK soil.
The current threat level for terrorism in the UK is severe, meaning an attack is highly likely.
The Metropolitan Police told people to "run, hide, tell" during the London Bridge attack in June 2017.
In May this year, counter-terrorism police published advice for people attending events in the UK over the summer.
What is the 'run, hide, tell' advice?
- Run: If there is a safe route, leave your belongings behind and run away. Insist others go with you, but don't let their indecision slow you down
- Hide: If you cannot move to safety, then hide somewhere with a solid, physical barrier between you and the attacker. Lock and barricade yourself in, turn your mobile phone to silent and stay quiet
- Tell: If you are in safe place, call the police with details of the attackers and location. The emergency number for EU countries is 112